How to get a song as a ringtone on Apple Music?

There are several, ringtone converters available from the App Store that can do that by only using your iPhone. Otherwise you will need a computer and follow these steps:

Create and manage ringtones - Apple Community

In any case, you cannot use an Apple Music subscription item, or anything that is in the cloud.. It will essentially have to be music you purchased from the iTunes Store or imported from another source (such as a CD).

Good Evening Maraven,

You'll find this article helpful when downloading or assigning ringtones.

Use tones and ringtones with your iPhone, iPad, or iPod touch - Apple Support

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